hwmon: (iio_hwmon) Add support for humidity sensors

The iio subsystem supports humidity sensors, so it makes sense
to support it in the iio-hwmon bridge as well.

Cc: Jonathan Cameron <jic23@kernel.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/iio_hwmon.c b/drivers/hwmon/iio_hwmon.c
index 14c82da..9801756 100644
--- a/drivers/hwmon/iio_hwmon.c
+++ b/drivers/hwmon/iio_hwmon.c
@@ -63,7 +63,7 @@
 	struct iio_hwmon_state *st;
 	struct sensor_device_attribute *a;
 	int ret, i;
-	int in_i = 1, temp_i = 1, curr_i = 1;
+	int in_i = 1, temp_i = 1, curr_i = 1, humidity_i = 1;
 	enum iio_chan_type type;
 	struct iio_channel *channels;
 	const char *name = "iio_hwmon";
@@ -123,6 +123,11 @@
 							  "curr%d_input",
 							  curr_i++);
 			break;
+		case IIO_HUMIDITYRELATIVE:
+			a->dev_attr.attr.name = kasprintf(GFP_KERNEL,
+							  "humidity%d_input",
+							  humidity_i++);
+			break;
 		default:
 			ret = -EINVAL;
 			goto error_release_channels;